The papers are the result of years of data collection stemming from an endeavor called HormoneBase, a living database spearheaded by Martin and other wildlife biologists. The database houses records of circulating hormones from free-living adult vertebrates (think fish, reptiles and birds).

“HormoneBase started out with about 15 members,” Martin said. “It was made up of graduate students, post docs and faculty from all different career stages. We scoured the literature, put together the architecture of the database and collated and curated it. Once we had the data—which consisted of 6,580 entries from 476 species across 648 papers and going back as far as 1967—we spent three days discussing what sort of insight we could glean from it. With a data set like that, an enormous number of questions came up. Everyone carved off a little slice of something they wanted to explore and it all culminated in the many articles in this particular journal issue,” he said. Much of Martin’s work centers around glucocorticoid stress hormones in vertebrates.

“Just as in humans, glucocorticoid hormones mediate the stress response in vertebrates,” explained Martin. “They are pumped into the blood by the adrenal glands to either help an animal get away from something threatening or to allow it to hunker down and preserve itself until danger passes. No matter what species we are talking about, the stress-mediating influences of glucocorticoid hormones are the same. It’s probably the most studied hormone in science, and that’s the major reason we decided to put the database together.”

“Basically we asked ourselves, ‘In species that are threatened with extinction, is there anything in their hormone levels that would predispose them to becoming extinct, compared to a species that is not threatened?’ In the end, we found the answer was no.”

HormoneBase is active and ongoing. As such, Martin notes, many more studies stemming from the database are now underway.